class Solution
{
public:
    long long flowerGame(int n, int m)
    {
        long long nOddCount = (n + 1) / 2;
        long long nEvenCount = n / 2;

        long long mOddCount = (m + 1) / 2;
        long long mEvenCount = m / 2;

        return nOddCount * mEvenCount + nEvenCount * mOddCount;
    }
};